Preliminary Investigation of the Audez'e LCD-3 and LCD-2 Page 2

THD+noise Measurements
Here's where things start to get a bit messy. I mentioned at the start that I've been measuring some Sennheiser HD 800s for a system characterization experiment. Here are the left and right THD+noise plots for the HD 800 with measurements taken on three different days during the same period I was measuring the LCD-3 headphones.

Here are the THD+noise at 90dB measurements of the four different LCD-3 headphones.

First, you'll notice the LCD-3 measurements are a lot more noisy and erratic than the HD 800. This measurement is very sensitive. If a truck goes down the street outside my house you'll see it here. It's also possible that noise on the incoming AC line might disturb these measurements. (I do have power conditioning, but I simply can't guaranty how well it performs.) It's exactly these kinds of results that have me investigating the performance of my system.

The problem is, while I do see some variability in the HD 800 THD plots of about the amplitude I'd expect, the variability of the LCD-3 plots is far wider. I usually leave the room during the THD plots, but in a couple of cases I was in the room sitting quietly watching as the plot was being taken. In one case (2312454C), I saw the elevated and noisy nature of the plot, and there wasn't any outside noise apparent. Plots like this could mean any number of things. To me, it looks like what I'd expect to see if something was rattling around inside the headphones around a certain frequency. For example, wires behind the driver might be moving about and making noise against something. That's just a guess though, just about anything could be going on. I don't really know what to say about the THD+noise graphs of the LCD-3s above, except to say the gear seemed to be working better than that when measuring the HD 800 (and other cans) that I was testing during the same period of time.

Apart from being erratic and noisy, some of the headphones exhibit a fairly wide noisy peak centered around 1.5kHz. It's not absolutely consistent, but this peak in THD+noise happens most on 2312260 and 2312476 --- the same two headphones without the frequency response step.

Good stuff Tyll. Really interesting. Looking forward to the data and trying out other headphones too. Makes me wonder just how much product to product variation there is out there for headphones in general?

While the THD numbers are not great, for sure. I'm more concerned with how poorly the drivers are matched.

Audeze does have wood throwing a curve on every headphone they make, but Hifiman and Beyer don't. Their phones are entirely metal or synthetic meaning a near perfect match for every headphone. Wood, as I know as a violin luthier, can be drastically different from one piece to the next. I'd still hope to see better numbers than this though.

From the experience in modifying vintage orthos reported in the 'ortho' thread at head-fi, the usual changes associated with damping done at the back of driver are tighter bass,increased upper mids & treble and a 'cleaner' sound overall.
The observations which support the underdamped state of some LCD-3's are:

1) Dip in upper mids
2) Less treble
3) Higher THD
4) reports of some pairs of LCD-3 sounding congested in complex passages.
5) Purrin's report over at head-fi in which he preferred his pair of LCD-3 after increasing damping with paper.

So infrequently do we see detailed exploration of this nature, and it's great to see your passion for audio is taking you here. Rather than just provide what you can completely explain, it takes courage to present what you know and listen for other thoughts from the crowd that could help to develop a more complete explanation. What do I need to do promote this research? Click links? Subscribe to something?

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Always enjoying your work Tyll...downright revolutionary in this particular field. And the other fellow at Head Fi, our Hero, also deserves accolades.

I should not care why a particular technology or design sounds good. Or bad. But I do care. Inquiring minds want to know.

It seems that measurements might give us some clues, at other times not much. And then we have the frustrating variability where the product reported on is not the product the consumer reading the review is listening to. Making fools of us all.

The fact is, the LCD-2 with its relatively minor shortcomings, is one of the most satisfying products I had ever heard - and evidently the minor shortcomings are EASILY cured by two items: the dragon slayer Silver Dragon wire from MOON, creating more presence, transparency, dimension and clarity, flattening the response by seemingly extending the top; and the parametric equalizers built into the iZotope engine of certain media players: Amarra and Fidelia come to mind, I'm not sure about the others.

Judiciously adjusted, the combination of the Dragon and media player may get the LCD-2 very close to the sound quality of the LCD-3... and you may be in the position to check me out on this issue.

While I can't speak for the potential of the LCD-3 but salivate at the thought, I do know that the potential of the LCD-2 cannot be achieved but by listeners trying out my suggestion above. The positive changes wrought to the LCD-2 (and I agree that the original sounded dark, although hardly veiled), is dramatic and real.

Anyhoo, it is trying, let me rephrase that, BORING, to listen to the disingenuous, lying Nattering Nebobs of Negativism - we know who they are, trolls - who don't own either product denigrate what they don't have (and likely never heard in their own systems), and of course, foolishly attempt to diminish those listeners who do.

These useless egoists just don't know how to enjoy life... and envy those who do.

Keep up the good work Tyll. Your arrival on the scene was just in time as this segment of the audio industry is heating up.

this is a comments thread not a "Team Audeze" or "Audeze Fan Club" thread. It follows Tyll Hertsen's preliminary investigations into claims of inconsistencies in the sound and frequency response of Audeze LCD-2 and LCD-3 headphones.

These claims are being made predominantly by the owners themselves and not by "disingenuous, lying Nattering Nebobs of Negativism", "trolls" and "useless egoists" as you so colourfully misrepresent them.

Fanatically barrack for your Audeze LCD-2, shower your "Hero" with bouquets and believe in the transformative powers of cables if you must. However, I'd like to think that a website devoted to headphones and ancillary gear would allow for the expression of rational critical and yes, contrary opinion, without summarily despatching the dissenters to a virtual gulag.

Otherwise, let's dispense with the charade of having comments threads and forums altogether and form fan clubs instead, where we can feel certainty in an uncertain world and take comfort from our shared belief that at least we own the "best" headphone in all of headphonedom, and bask in its reflected glory.

And again for the upteenth time AGB, I have heard the LCD-2. I was impressed with some aspects of its performance, but not enough to want to buy one. Nor do I envy those who have, including you.

Tyll,
Does your setup produce any raw data (audio files) from the THD frequency sweeps? If so, I (and others probably) would like a crack at extracting more information from them, to get a better understanding at what is going on with these LCD3 "THD+noise measurements that seem rather random" and answering questions such as "Maybe it's even-harmonic distortion?".

First, thank you for all the great writing and testing you do. I own a pair of LCD-3s from the first batch that shipped, and (like many other LCD-3 owners and potential buyers) I'm very concerned about the reports of significant sound quality variances between units. Your investigation will hopefully help us get to the bottom of the problem.

I have no background or knowledge from which to interpret your data, so please forgive my ignorance but I'm confused by some of the data and how they reinforce or contradict what you hear during listening tests.

You said that the 2 LCD-3s with a more pronounced dip between 2-3kHz are the same ones that sounded "more present" with female vocals. Wouldn't the headphones with a larger dip in the upper midrange have vocals that sound more recessed/veiled?

Also, the other 2 headphones you tested have more significant THD+noise peaks, but their frequency response graphs are smoother (especially in the 2-3kHz range). What, if any, noticeable effect on sound quality would a high THD+noise peak have on the sound? Are THD+noise and frequency response totally unrelated?

Finally, are the pictures of the LCD-3 cups that you posted on page 2 of the report from different units, or the same headphone? It looks to me as though the earpad on the right cup is substantially thicker. There is some talk now on Head-fi that the difference in earpad foam thicknesses may be to blame; what do you think of this theory?

Maybe I wasn't cear enough, but the feature that's most easily seen in the FR curves is the drop between 3kHz and 4kHz. The drop happens because those cans are carrying more energy between 2kHz and 3kHz --- making them sound a little more present. The green and orange traces in this graph.

"What, if any, noticeable effect on sound quality would a high THD+noise peak have on the sound? Are THD+noise and frequency response totally unrelated?"

Harmonic distortion typically has a harsh, annoying sound. But the THD+noise measurement could be odd-harmonics; even-harmonics; and/or noise from a variety of sources. The point is there's no telling from the curve what the effect on the sound will be. It's just elling us there some extranious sound that shouldn't be there ideally.

The headphones in the picture are the LCD-2 on the left and the LCD-3 on the right. THe LCD-3 has thicker and softer pads. Pads do have significant effect on the sound. My tendency is to think the erratic results I got in the THD+noise measurements is unrelated to the pads. My guess is that it's more driver related.

We apologize for our lack of communication while we have researched what caused a small percentage of our LCD-3 headphones to fail. Our headphones are fully warrantied and we will replace these failed LCD-3s at no cost to our customers. Part of the reason why our headphones are expensive is the cost of materials, craftsmanship and intricate technology that goes into each and every product we make. Our headphones are built for the discriminating listener, who demands impeccable quality. As such, the moment we heard that there had been failures, we halted LCD-3 production and spent the past several weeks examining every material and process in detail to find and eliminate the issue. Having found and fixed this issue, we are restarting production and will deliver replacements to our customers who have experienced problems. As part of our attempts to address the issue, we are also extending the warranty on our LCD-3 to three years.

We were deeply distressed to find that a small portion of material we received from one of our vendors ended up having imperfections that, despite our extensive quality control processes, we could not detect at the time. While the headphones performed flawlessly in the lab, a combination of rough handling and rapid changes in temperature and pressure during shipment caused some units to fail. These failures occurred either immediately or, in a few instances, shortly after a customer's first use. The relatively low failure rate and the combination of circumstances necessary to cause this type of failure made locating the problem a much lengthier process than we would have liked.

We have since discarded all the components in the defective batch, and have developed a new process for vetting vendor supplies to prevent this problem from recurring. We have also completely redesigned our quality control procedures. As we bring our LCD-3 production back online, we will be able to deliver replacements for those in need.

We stand by our product and want to ensure that you are completely satisfied. Working at the extreme edges of technology and performance is difficult, expensive and time consuming. Our company is owned and run by audio enthusiasts like you, and we deeply regret the problems any of our customers have experienced. While the majority of LCD-3s work properly, to demonstrate our faith in our product and to allay any further concerns, we have extended our warranty for the LCD-3 to three years from purchase. If you have experienced any issues, or are concerned about the performance of your LCD-3, please contact us at support@audeze.com so that we may be able to immediately rectify the situation. As always, we value this community and thank you for your continued support.